Considering Thanos [SPOILER - highlight to read]: was getting raped by Wanda and Captain Marvel was no-selling his unamped attacks I think it's safe to say Doomsday slaughters.
They would beat Doomsday in that scenario under the circumstances considering the sjw in marvel.
You can’t not take into account the fact that [SPOILER - highlight to read]: Thanos was on the verge of killing dual hammer wielding Thor , broke caps shield in2 and easily handled Hulk like a kid
Insane Titan, [SPOILER - highlight to read]: Endgame Thor was fat and drunk. He was so out of his prime it's not even funny. And what's Cap's shield's best durability feat? Taking a hit from Mjolnir. Nice but nothing special. Certainly nothing on the level of taking a nuke.
Hulk has jobbed to Hulkbuster, so while it's a nice feat, it's nothing to someone who eats nukes for breakfast.
Thanos' power was all over the place[SPOILER - highlight to read]: He goes from taking on Captain America and Thor at the same time w/o stones but gets nearly beaten by Wanda and Captain Marvel was able to overpower him while having the stones equipped...even no selling his unamped punch
[SPOILER - highlight to read]: Thor was past the fat and drunk stage whenThanos wrecked him. He was fully charging with electricity wielding both hammers The hulk only lost to hulk buster after a long fight , big difference from a Thanos doing it with such ease. If you’re going down the road of lowballing the shield. Thor tanked a star and he wasn’t able to handle Thanos for as long as he did the stars force.
DD lost a arm from Diana’s sword, Thanos infinity sword would do far more damage.
[SPOILER - highlight to read]: Thanos basically had a metal equivalent of Darth Maul's lightstaff (Quan is gonna love it), not sure what is a proper name for such weapon. We'd need to ask anime fans.